Inresponsetothecallforpapers39weresubmittedtoCMSB2003. Allthe submittedpaperswerereviewedandtheprogrammecommittee(listedbelow) selected11high-qualitypapersforpublicationinthisvolume. Thecareofthe reviewersandoftheprogrammecommitteemembersinreviewingthepapers wassurelyvaluable. Afurther11paperswereselectedonlyforpresentationat theworkshopinordertostimulatediscussions(anabstractisincluded). AttheworkshopEhudShapiroandMichaelSterngavetwoinvited talks whosetopicsaredescribedinpapersincludedinthisvolume. Theprogramme committeedecidedtoacceptforpublicationinthisvolumealsosomeposition papers that highlight the research trends in this new ?eld of computational methodsinsystemsbiology. Thereasonisthatbecausethisisthe?rstedition ofaworkshopinthisfast-growing?eldalargeviewofpotentialtopicsofresearch wasconsideredextremelyimportant. Rovereto, December2002 CorradoPriami ProgrammeCommitteeofCMSB 2003 CorradoPriami(Chair), UniversityofTrento(Italy), CharlesAu?ray, CNRS, Villejuif(France), CosimaBaldari, Universit`adiSiena(Italy), AlexanderBockmayr, Universit¿eHenriPoincar¿e(France), LucaCardelli, MicrosoftResearchCambridge(UK), VincentDanos, Universit¿eParisVII(France), PierpaoloDegano, Universitad ` iPisa(Italy), Francois ¿ Fages, INRIA, Rocquencourt(France), DrabløsFinn, NorwegianUniversityofScienceandTechnology, Trondheim(N- way), MonikaHeiner, BrandenburgUniversityofTechnologyatCottbus(Germany), InaKoch, UniversityofAppliedSciencesBerlin, (Germany), JohnE. Ladbury, UniversityCollegeLondon(UK), PatrickLincoln, SRI(USA), SatoruMiyano, UniversityofTokyo(Japan), GordonPlotkin, UniversityofEdinburgh(UK), SimonPlyte, PharmaciaCorporation(Italy), AvivRegev, WeizmannInstituteofScience(Israel), MagaliRoux-Rouqui¿e, BSMIPasteurInstitute(France), VincentSchachter, HybrigenicsParis(France), MasaruTomita, KeioUniversity(Japan), AdelindeUhrmacher, UniversityofRostock(Germany), AlfonsoValencia, CNB-CSIC, CentroNacionaldeBiotecnologia(Spain), OlafWolkenhauer, UMIST, Manchester(UK) Local Organizing Committee Corrado